What would be the reason behind using plots (such as box-plots or histograms) for ML development?
At a basic level, these kinds of low-dimensional plots where you look at one or two variables at a time can help to give you a sense of what types of relationships you might expect to see, such as linear, non-linear, or periodic relationships, which can steer you toward an appropriate family of models. You wouldn't want to use a linear model to predict data that has highly non-linear relationships, for example, nor would you want to use a monotonic non-linear model to predict a periodic function like a sine wave. Knowing about the general distribution of certain variables can also give you a sense of what statistical assumptions might or might not be met - if a model assumes that data is normally distributed, it might not be appropriate if your histograms suggest otherwise. Statistical analysis can help you determine if the underlying assumptions for certain model classes are or are not met.